The newly released audio is a 5-minute recording of Zimmerman yelling help almost two dozen times and then help me several more times. The audio includes lengthy portions of silence.

The two voice samples were taken in March and used by the state attorney's office to figure out who on the 911 tape was screaming for help Zimmerman or Trayvon Martin.

An investigator calls a dispatcher at the sheriff's office and asks them to make the recording.

"We're getting ready to do it and basically we're just going to have the gentleman reenacting a few things," said the investigator on the recording. "You'll hear some yelling and things like that but no need to interrogate us or to call or anything. We're going it for recording purposes."

In a previous bond hearing, the FBI investigators who analyzed the voice samples said it was inconclusive who was screaming on the recordings.

All of the discovery evidence was ordered to be released by Judge Kenneth Lester.

Also on Wednesday, Mark O'Mara filed a motion to have Zimmerman appear in civilian clothing and without restraints at the bond hearing on Friday.

O'Mara said that Zimmerman's portrayal by the "media will have a tremendous impact on his ability to receive a fair trial" and that him being shown in shackles and a jail uniform is allowing him to be prejudged by the public.

At his last bond hearing, Zimmerman was allowed to wear a suit but his hands were cuffed to a chain around his waist and his ankles were shackled.